Optical radiation sensing properties of MnO/TeO2 thin films

This work investigates the effects of gamma-rays on the optical properties of pure and mixed-oxide materials, namely MnO and TeO2, for their possible application as thin film optical gamma radiation sensors. The values of the optical band gap E-opt were obtained in view of the Mott and Davis theory. All samples showed a decrease in E-opt with an increase in radiation dose to a certain level, which was found to be composition dependent. Films with 100 wt. % MnO exhibited the highest sensitivity to low doses of radiation, showing a strong decline in the optical band gap value from 0.64 eV before irradiation to 0.54 eV after a dose of 1.14 mGy. It was experimentally confirmed that both the sensitivity and the working dose range of radiation sensors can be controlled by the composition of the materials used.